Recent advances in catalytic asymmetric metalloid–hydrogen bond insertion of transition-metal carbenes

Over recent decades, transition-metal-catalyzed asymmetric carbene insertion into metalloid-hydrogen bonds (B-H/Si-H/Ge-H) has become a prominent research area. This review summarizes recent enantioselective strategies for constructing chiral organoboron, organosilicon, and organogermanium compounds through carbon-metalloid bond formation. Approaches are classified by chirality induction modes, with emphasis on transition-metal catalysts paired with precisely designed chiral ligands, including bisoxazolines, dienes, carboxylates, and diimines. Mechanistic correlations between ligand architectures and stereocontrol are discussed. Additionally, environmentally friendly biocatalytic approaches using engineered enzymes are also highlighted.